Held ball without holding?

[phansen]

NFHS

During a loose ball A1 somehow ends up rolling on his back with the ball between his mid back and the floor. A1 cannot reach around himself to
grab the ball but has it pinned to the floor and seems satisfied not to move. B1 reaches under A1 and grabs the ball but cannot free it.
Held ball??
This situation doesn't meet all the 4-25 definition, but I called a held ball.